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Fragmentation extent of six ecosystem types after European Settlement was analyzed using LANDFIRE data. The ecosystem types includes: Grassland, Shrubland, Conifer, Riparian, Hardwood and Sparse ecosystems. The land use change and fragmentation extents have been analyzed by delineating nine Greater Wildland Ecosystems (GWEs) across NCCSC.
Conclusions:Forest clearcutting differentialy affects birds of different ages. There is a threshold distance between reserves below which birds do not mind crossing clear cuts, making corridors more important as clearcut area and distance between forest reserves expandsThresholds/Learnings:
Conclusions:Results indicated that system and species-specific considerations are important when assessing the potential outcome of habitat loss and fragmentation on regional biotaThresholds/Learnings:
Climate changes impose requirements for many species to shift their ranges to remain within environmentally tolerable areas, but near-continuous regions of intense human land use stretching across continental extents diminish dispersal prospects for many species. We reviewed the impact of habitat loss and fragmentation on species? abilities to track changing climates and existing plans to facilitate species dispersal in response to climate change through regions of intensive land uses, drawing on examples from North America and elsewhere. We identified an emerging analytical framework that accounts for variation in species' dispersal capacities relative to both the pace of climate change and habitat availability....
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Climate change, drought, habitat alterations, and increasing water demands are leaving less water available for streams of the Pacific Northwest and for fish like salmon. As water levels drop, some small streams become fragmented, transforming from a ribbon of continuous habitat into a series of isolated pools. Fragmented streams may pose a serious threat to salmon. For example, juveniles that become stranded in small pools are at increased risk to overheat, starve, or be consumed by predators. Healthy salmon populations can cope with fragmentation and recover from a bad drought-year. However, many salmon populations are endangered and face long-term drought. Land and resource managers are increasingly finding...
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This dataset displays the boundaries of Intact Forest Landscapes for the islands in the Tongass region of the state of Alaska. Intact Forest Landscapes for islands are defined as areas at least 500 hectares that are absent of human disturbance visible on satellite imagery (e.g., roads, logging, mining, settlement). For more information, see the full report, available on the Global Forest Watch website (www.globalforestwatch.org), or the Conservation Biology Institute website (http://www.consbio.org/cbi/projects/show.php?page=alaska).
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The Wildland-Urban Interface (WUI) is the area where houses meet or intermingle with undeveloped wildland vegetation. This makes the WUI a focal area for human-environment conflicts such as wildland fires, habitat fragmentation, invasive species, and biodiversity decline. Using geographic information systems (GIS), we integrated U.S. Census and USGS National Land Cover Data, to map the Federal Register definition of WUI (Federal Register 66:751, 2001). These data are useful within a GIS for mapping and analysis at national, state, and local levels.
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Conclusions: Grizzly bears avoid high volume roads (25,000 vehicles/day). High quality habitat determines movement decisions relative to roads. Grizzly bears will cross high volume roads to access high-quality habitat. Grizzly bears use areas close to roads more than expected, in particular low-volume roads (10,000 vehicles/day). Prevent loss of habitat connectivity with the following mitigation: maintain high-quality habitat adjacent to roads, install continuous highway fencing and create wildlife passages. Thresholds/Learnings: Synopsis: The study examined the relationships among grizzly bears, their habitats and roads in Banff National Park, a protected area characterized by a major transportation corridor. This...
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Conclusions: The negative effects of patch size and isolation on species may not occur until the landscape consists of less than 10% suitable habitat for birds, and 30% suitable habitat for mammals. Thresholds/Learnings: The negative effects of patch size and isolation on species may not occur until the landscape consists of less than 10% suitable habitat for birds, and 30% suitable habitat for mammals. Synopsis: This study involved a review of studies on birds and mammals in habitat patches in landscapes with different proportions of suitable habitat. The findings demonstrate that there exists a threshold in proportion of suitable habitat in the landscape, above which fragmentation becomes pure habitat loss....
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Habitat fragmentation and degradation are considered to be a leading causes of long-term population declines of Northern Bobwhites and many other species of grassland birds, such as Eastern Meadowlark. Research is needed to understand the factors causing habitat loss and fragmentation and to identify the areas that are high-probability candidates for successful restoration so that optimal decisions can be made. For example, uncertainty exists regarding the impacts of energy development activities or climate change that affect significant portions of wildlife populations in the GCP LCC. Furthermore, changing land ownership coupled with woody shrub and exotic grass encroachment have reduced the amount and quality...
Categories: Data, Project; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: 2015, 2016, Academics & scientific researchers, Conservation Design, Conservation NGOs, All tags...
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Probability of Development, Northeast U.S. is one of a suite of products from the Nature’s Network project (naturesnetwork.org). Nature’s Network is a collaborative effort to identify shared priorities for conservation in the Northeast, considering the value of fish and wildlife species and the natural areas they inhabit. This index represents the integrated probability of development occurring sometime between 2010 and 2030 at the 30 m cell level. It was based on models of historical patterns of urban growth in the Northeast, including the type (low intensity, medium intensity and high intensity), amount and spatial pattern of development, and incorporates the influence of factors such as geophysical conditions...
This cooperative effort by USDA Forest Service Research and the National Forest System assesses the state of knowledge related to the conservation status of four forest carnivores in the western United States: American marten, fisher, lynx, and wolverine. The conservation assessment reviews the biology and ecology of these species. It also discusses management considerations stemming from what is known and identifies information needed. Overall, we found huge knowledge gaps that make it difficult to evaluate the species' conservation status. In the western United States, the forest carnivores in this assessment are limited to boreal forest ecosystems. These forests are characterized by extensive landscapes with...
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Simple road density calculated as miles of road per square mile. Thus, a 1 square mile circular window was used to sum the length of road for each 30 meter cell. I relied only on Clearwater and Nez Perce National Forest roads datasets.
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Conclusions: When isolated, larger patch size correlates with higher species density and occurence in area-sensitive grassland birds Thresholds/Learnings: Synopsis: This paper examines the influence of landscape fragmentation and isolation of Conservation Reserve Program (CRP) grasslands on grassland breeding bird populations in the northern Great Plains states. The study explores the relationship between species occurrence and density, and patch size by tracking 15 bird species on 303 restored grassland areas. Locating CRP grassland fields near existing grasslands, or establishing one large CRP field rather than several small fields, benefits area-sensitive grassland bird species. Caveats: Inconsistent findings...
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Synopsis: This study examines the influence of landscape fragmentation on trophic cascades in southern California. Results indicate that, as habitat fragmentation negatively affects the persistence of coyote populations, the abundance of smaller meso-predators increase, resulting in higher mortality rates in scrub-breeding birds. Fragment size was a strong indicator of coyote abundance, and coyote abundance was a strong indicator of bird diversity, as coyotes kept down the number of meso-predators that prey on birds. The positive effect of fragment area and the negative effect of fragment age were the strongest determinants of bird diversity in this system. Conclusions: Fragment size correlates with coyote abundance,...
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Conclusions: Summarizes findings from a review of literature intended to identify critical thresholds for conservation based in empirical studies of landscape fragmentation. Presents a conceptual overview of landscape fragmentation and habitat loss, as well as guidelines and thresholds relating to landscape indicators such as patch size, habitat amount, edge effects, riparian buffers, and habitat connectivity. Thresholds/Learnings: Many. See Kennedy et al. 2003. Synopsis: This report summarizes findings from a review of literature intended to identify critical thresholds for conservation based in empirical studies of landscape fragmentation. In presenting a conceptual overview of landscape fragmentation and habitat...
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This map layer is a grid map of the conterminous United States, created from National Land Cover Data (NLCD). The NLCD data was reclassified into four categories: forest, other natural (e.g. grassland, wetland, etc.), human land use (e.g. agriculture, urban, etc.), and nodata (water, ice and snow, and bare rock/sand). A 9 x 9-pixel moving window was then used to generate forest edge measurements for every pixel, regardless of its class. Within each window, the edges of all forest pixels were examined to determine what type of land cover shared each edge. Three new grids were created, one for each edge type (forest-forest, forest-natural, and forest-human)....
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Fragmentation extent of six ecosystem types after European Settlement was analyzed using LANDFIRE data. The ecosystem types includes: Grassland, Shrubland, Conifer, Riparian, Hardwood and Sparse ecosystems. The land use change and fragmentation extents have been analyzed by delineating nine Greater Wildland Ecosystems (GWEs) across NCCSC.
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Conclusions: At small spatial scales, where extirpation risks are high, landscape fragmentation will likely have long-term negative consequences on the genetic variation of individual assemblages of coastal cutthroat trout. Thresholds/Learnings: Synopsis: This study aimed to determine if coastal cutthroat trout were genetically structured within streams and to assess the effects of habitat fragmentation on coastal cutthroat trout genetic variation. Habitat fragmented by roads and other human disturbances acted as dispersal barriers, which strongly influenced coastal cutthroat trout genetic structure, diversity, and differentiation. At range-wide spatial scales, fragmentation potentially contributes to coastal cutthroat...
Synopsis: This book provides important foundational concepts in landscape ecology, with a particular focus on the effects of land use and landscape fragmentation. Building on Forman’s patterns of landscape change, the book cites the McIntyre and Hobbs model of landscape change, which suggests that landscape modification often increases through time. Four broad classes of landscape condition can therefore be identified along a continuum of increasing human landscape modification: intact, variegated, fragmented, and relictual (figure 3). Similarly to Forman’s model, these classes represented correspond to different spatial patterns in the landscape. Therefore, as the extent of human land use increases, the amount...
map background search result map search result map Causes of Forest Fragmentation in the United States – 270 Meter Resolution Area requirements of grassland birds: a regional perspective. Conservation Thresholds for Land Use Planners Influences of barriers to movement on within-watershed genetic variation of coastal cutthroat trout Relationships among grizzly bears, highways, and habitat in Banff-Bow Valley, Alberta, Canada. Effects of habitat fragmentation on birds and mammals in landscapes with different proportions of suitable habitat: a review. Mesopredator release and avifaunal extinctions in a fragmented system. Road Density Across the Clearwater Basin National Forests Alaska's Intact Forest Landscapes - Tongass (Islands) Habitat Loss and Fragmentation Effects in the Management of Northern Bobwhites and Eastern Meadowlarks Evaluating the Effectiveness of Assisted Migration and Fish Rescue Programs Probability of Development, 2030, Version 3.1, Northeast U.S. Land use change and fragmentation of Rocky Mountain Greater Wildland Ecosystems (GWE) using LANDFIRE data Land use change and fragmentation of Theodore Roosevelt Greater Wildland Ecosystems (GWE) using LANDFIRE data BLM REA SLV 2013 WUI Poly (WUI Classes) Influences of barriers to movement on within-watershed genetic variation of coastal cutthroat trout Relationships among grizzly bears, highways, and habitat in Banff-Bow Valley, Alberta, Canada. BLM REA SLV 2013 WUI Poly (WUI Classes) Road Density Across the Clearwater Basin National Forests Land use change and fragmentation of Rocky Mountain Greater Wildland Ecosystems (GWE) using LANDFIRE data Land use change and fragmentation of Theodore Roosevelt Greater Wildland Ecosystems (GWE) using LANDFIRE data Evaluating the Effectiveness of Assisted Migration and Fish Rescue Programs Alaska's Intact Forest Landscapes - Tongass (Islands) Mesopredator release and avifaunal extinctions in a fragmented system. Habitat Loss and Fragmentation Effects in the Management of Northern Bobwhites and Eastern Meadowlarks Area requirements of grassland birds: a regional perspective. Probability of Development, 2030, Version 3.1, Northeast U.S. Causes of Forest Fragmentation in the United States – 270 Meter Resolution Conservation Thresholds for Land Use Planners Effects of habitat fragmentation on birds and mammals in landscapes with different proportions of suitable habitat: a review.